• Title/Summary/Keyword: horn

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A Simple Arthroscopic Resection Technique for Inferior Leaf of the Deep Horizontal Tear in the Anterior Meniscal Horn - Technical Note - (반월상 연골 전각의 깊은 수평 파열에서의 간단한 관절경 하부 연골편 절제술 - 수술술기 -)

  • Lee, Kee-Byoung;Lee, Seok-Beom;Chang, Ho-Guen;Moon, Young-Wan;Kang, Ki-Hoon;Kim, Kye-Won
    • Journal of the Korean Arthroscopy Society
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    • v.3 no.1
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    • pp.62-65
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    • 1999
  • A new method for arthroscopic resection of the inferior leaf for the horizontal tear in the anterior horn of the meniscus extending deep toward the capsule was developed. Resection of this tear is difficult-perhaps more so than any other meniscal tear. At arthroscopy, a small incision on the meniscotibial ligament of the anterior horn was made after the deep horizontal tear was carefully debrided. A retrograde punch was introduced through the incision and underneath the inferior leaf of the anterior meniscus. The inferior leaf of the anterior horn was resected by the punch without difficulty. This simple technique minimizes the risk of superior leaf injury and can be used for a horizontal tear in the anterior horn as well as the mid horn with sweeping motion of the retrograde punch.

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Design of Data Transmission Corrugated Horn Antenna for RF Sensor Satellite System (RF센서 위성시스템용 데이터 전송 컬러게이트 혼 안테나 설계)

  • Jeon, Jung-Ik;Choi, Hak-Keun;Lim, Seong-Bin;Jang, Jae-Woong;Kim, Tae-Yoon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.11 no.3
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    • pp.1-8
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    • 2011
  • In this paper, data transmission corrugated horn antenna for RF sensor satellite system and its radiation characteristic are presented. The proposed antenna is designed, fabricated and measured to obtain the maximum gain at ${\pm}60^{\circ}$ of its radiation patterns. The result of the proposed antenna is that the return loss is less than -15 dB and the gain is over 5 dBi at ${\pm}60^{\circ}$ of its radiation patterns. From these results, it is confirmed that the proposed can be used as data transmission corrugated horn antenna for RF sensor satellite system.

Front-to-Back Ratio Improvement of a High-Power Horn Antenna (고출력 혼 안테나의 후엽감쇄 연구)

  • Shin, Jae-Yoon;Shim, Hong-Suk;Lee, Byung-Hyun;Lee, Jung-Ran;Woo, Jong-Myung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.29 no.5
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    • pp.389-392
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    • 2018
  • Herein, a horn antenna that has the maximum back lobe reduction characteristic using a corrugated structure at 1.57 GHz for a high-power microwave system is proposed. The back-lobe characteristics of the proposed antenna was optimized using simulation as the number of corrugated structures increase, and the three-staged corrugated structure was designed. Consequently, the front-to-back ratio(FBR) of the fabricated antenna is 47.2 dB, which is improved by 23.7 dB based on that of the basic horn antenna, i.e., 23.47 dB.

A Study on the Characteristics of the Excited Vibration Signals in a Thermosonic Test (초음파가진 열화장시험 시 가전된 진동 신호 특성 연구)

  • Kang, Bu-Byoung
    • Journal of the Korean Society for Nondestructive Testing
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    • v.31 no.2
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    • pp.118-126
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    • 2011
  • The characteristics of the responses obtained in thermosonic tests are investigated in this study to improve the performance of a thermosonic test system. Thermosonic tests are conducted with an acoustic horn with high power capability to investigate the characteristics of the vibration produced in turbine blades with complex geometry. The influences of the excitation signal that is input to the horn and the coupling methods between a clamp and the acoustic horn on the characteristics of the vibration excited in a component are presented. As a result, an excitation method with a fast narrow band chirp test (sweep test) and a stud coupling is proposed as an excitation method for thermosonic testing. This method can be applied to different types of turbine blades and also to other components.

A Filtering Antenna for Wireless In-Flight Entertainment Communication System at Millimeter-Wave Band (기내 엔터테인먼트 통신 시스템을 위한 밀리미터파 대역의 여파기 결합 안테나)

  • Seo, Tae-Yoon;Lee, Jae-Wook;Cho, Choon-Sik
    • Journal of Advanced Navigation Technology
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    • v.14 no.1
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    • pp.11-19
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    • 2010
  • In this paper, H-plane filtering-horn antenna operating at millimeter frequency band is proposed with embedded filter and three-layered dielectric lens for frequency selection and maintenance of main beam direction, respectively. The waveguide-typed filter and H-plane sectoral horn antenna are replaced with considerably size-reduced PCB substrate-typed filtering antenna using via fences and several posts. The waveguide-typed filter and H-plane sectoral horn antenna were designed in air-filled waveguide and then combined into size-reduced PCB substrate. For the control of the thickness of dielectric lens, single and multi dielectric lens have been employed. As a result of antenna gain, 8 and 13.5 dBi have been obtained at 41.5 GHz, respectively, from the simulations of single and multi-lens antennas.

Optimal Welding condition in Ultrasonic Welding of Ni steel sheet (Ni 박판의 초음파 용착시 최적용착 조건)

  • Seo, Jeong Seok;Park, Dong Sam
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.9 no.2
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    • pp.47-52
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    • 2010
  • Miniaturization and lightweight are increasingly the recent trend in the manufacture of electric appliances and machine parts. So technology of micro joining for joining materials is indispensable. This paper gives a description of an experimental study of the ultrasonic welding of metals. In ultrasonic metal welding, high frequency vibrations are combined with pressure to join two materials together quickly and securely, without producing significant amount of heat. Ultrasonic metal welder consists of Transducer, Booster, and Horn that are designed very accurately to get the natural frequencies and vibration mode. In this study, The horn was designed and analyzed the natural frequency by the modal analysis and harmonic analysis. And using a fiber optic sensor, we measured the amplitude and analyzed the Fast Fourier Transformed result. Using the horn, Ultrasonic metal welding between Ni sheet and Ni sheet of 0.1mm thickness was accomplished under the optimal conditions of static pressure 0.15MPa, vibration amplitude 45% and welding time of 0.28s. This result can be used for ultrasonic metal welding in manufacturing industry.

Detectivity Improvement of Microbolometer by Coupling 3D Feed Horn Antenna (3차원 피드 혼 안테나 결합을 통한 볼로미터의 감지도 향상)

  • Kim, Kun-Tae;Park, Jong-Yeon;Moon, Sung;Park, Jung-Ho;Park, Jong-Oh
    • Proceedings of the KIEE Conference
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    • 2001.07c
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    • pp.1899-1901
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    • 2001
  • 본 논문에서는 3차원 feed horn 안테나를 볼로미터에 결합함으로써 감지도(Detectivity)를 향상시킨 비가시광 영상 감지 소자를 제안하였다. Feed horn 안테나의 우수한 지향성(Directivity)를 통해서 주위의 잡음 성분을 제거함으로써 감지도의 향상을 확인할 수 있었다. 안테나와 볼로미터와의 결합 손실을 줄이기 위해서 볼로미터의 흡수층의 모양을 원형의 형태로 하였으며 크기도 안테나 폭과 일치를 시켰다. 또한 열적 고립 구조를 만들기 위한 지지 다리의 모양도 원형의 형태로 하여서 전체 길이를 증가 시켰으며 이로 인해 열전도도(Thermal conductance)를 $4.65{\times}10^{-8}$[W/K]까지 낮출 수 있었 다. 설계된 소자의 감지도는 $2.37{\times}10^{9}$[$cm\sqrt{Hz}/W$]을 나타내었으며 안테나 결합을 통한 감지도의 향상을 확인 할 수 있었다. 볼로미터의 제작은 MEMS 기술을 이용한 표면미세가공(Surface micromachining)법으로 열적 고립 구조체를 제작할 수 있으며 3차원 feed horn안테나는 SU-8이라는 음성 감광제를 경사회전노광시켜서 제작할 수 있다.

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